public static void Prim(

int src,

ArrayList<ArrayList<Node>> graph,

ArrayList<Integer> distArr,

ArrayList<Boolean> visitedArr,

ArrayList<Integer> pathArr) {

PriorityQueue<Node> pq = new PriorityQueue<Node>();

pq.add(new Node(src, 0));

distArr.set(src, 0);

int u, v, w;

while (!pq.isEmpty()) {

Node top = pq.poll();

u = top.id;

visitedArr.set(u, true);

for (int i = 0; i < graph.get(u).size(); i ) {

Node neighbor = graph.get(u).get(i);

v = neighbor.id;

w = neighbor.dist;

if (!visitedArr.get(v) && w < distArr.get(v)) {

distArr.set(v, w);

pq.add(new Node(v, w));

pathArr.set(v, u);

}

}

}

}

public static long weigthMST(ArrayList<Integer> distArr, ArrayList<Integer> pathArr) {

long ans = 0;

int n = distArr.size();

for (int i = 1; i < n; i ) {

ans = (long) distArr.get(i);

}

return ans;

}

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

int n = sc.nextInt();

int m = sc.nextInt();

ArrayList<ArrayList<Node>> graph = new ArrayList<>();

ArrayList<Integer> distArr = new ArrayList<>();

ArrayList<Boolean> visitedArr = new ArrayList<>();

ArrayList<Integer> pathArr = new ArrayList<>();

for (int i = 0; i < n 1; i ) {

graph.add(new ArrayList<Node>());

visitedArr.add(false);

pathArr.add(-1);

distArr.add(Integer.MAX_VALUE);

}

int u, v, w;

for (int i = 0; i < m; i ) {

u = sc.nextInt();

v = sc.nextInt();

w = sc.nextInt();

graph.get(u).add(new Node(v, w));

graph.get(v).add(new Node(u, w));

}

Prim(1, graph, distArr, visitedArr, pathArr);

System.out.println(weigthMST(distArr, pathArr));

}

int id, dist;

public Node(int id, int dist) {

this.id = id;

this.dist = dist;

}

public int compareTo(Node other) {

return this.dist - other.dist;

}